The
insulation used for the bathroom ceiling and the bathroom end walls was the same as I
would use for the remainder of the living area. After fitting the ply-lining and false
ceiling, I drilled several 10mm diameter holes in convenient locations and injected
through them copious amounts polyurethane expanding foam. The idea was to completely fill
the void spaces and create a layer of very efficient thermal insulation.

Following insulation, the bathroom walls and ceiling have been lined
with vinyl floor covering. It is waterproof and hardwearing. I used contact adhesive to
hold it in place.

A word of warning: Contact adhesive does not tolerate any errors in
fitting! You have one chance to get the stuff in the right place and that is it!